I am in search of an internally regulated alternator schematic. Anybody have one? Know where to find one?

Reason is to try and understand, at the component level, why you can use the gen light to excite the alternator. Also, why sometimes you need to place a diode in line with the excitation wire to not allow run-on. Yes, I can read a million threads on the internet about how to wire it, but not many people can explain why (from the regulator stand point)......

No kidding... I've got a stack (2 piles, 3 feet high) of Chilton, Motor, or OEM manuals from the 50's to the 80's. They are a huge resource of info, back from the day when people actually fixed things, instead of amputating at the largest sub-assembly and replacing.